Vitus Bikes has kicked another goal with the Zenium SL, a fast endurance bike with the superior stopping power of disc brakes, a fun and fast frame and an excellent-value spec.
Inevitably, the first thing you notice about the Zenium SL Disc is that screaming bright ORANGE paint job. Loud colours are front and centre in the 2017 Vitus range; the Energie Cyclo X we tested is similarly decked out in an extraordinary green that really is as bright in the metal as it looks in our photos.
Ultra-bright colours aren't to everyone's taste, but the Zenium SL Disc's finish makes me smile every time I look at it, and that's got to be a good thing.
The Zenium's ride will make you smile too. It's quick without being harsh or hairy, and rolls beautifully on its Michelin Pro 4 Service Course tyres. Until they were replaced by the Power Competition model, these were Michelin's top high-performance tyres. They provide excellent grip and roll quickly and smoothly thanks to their supple casing. I sustained more punctures on these tyres than I'd expect during the test period's dry weather, but it's likely I just got unlucky. Tyre guru Jarno Bierman found the Pro 4's puncture resistance was better than that of a Continental GP4000S II.
In every other respect the Zenium is a big orange bundle of fun that's quick on the flat, grin-inducingly swoopy on twisty descents, and civilised on climbs. You don't expect an almost-9kg bike to fly up hills, but the Zenium doesn't feel sluggish climbing, just calm and measured, and it's plenty stiff too.
I had one of the most fun rides I've done in ages aboard the Zenium SL. I was coming back to Cambridge from riding with friends in South London, when my train stopped at Welwyn Garden City. Thanks to an incident at Knebworth it looked like we weren't going any further, and might even have to go back to King's Cross to take a different route north. I decided I'd ride the rest of the way. After all, it's just a bit under 40 miles or so.
By this time, it was late evening. Not quite getting dark, but dusk wasn't far away. No problem, I had lights. I thought I was in for an hour and a half or so in actual darkness, at most.
Welwyn Garden City to Cambridge might be under 40 miles by car, but it's nearer 50 if your Garmin is loaded with Open Street Map cycling maps that carefully route you off main roads. What followed was a hugely enjoyable voyage of discovery through tiny villages and along lanes and minor B-roads, mostly in the dark. By the time I got home, it was almost midnight.
Floating through the dark on the Zenium SL, I felt a kinship to the ultra-distance riders I've long admired. This must be what it's like to be Kristoff Allegaert or Juliana Buhring, I thought. Then I remembered they'd be doing 30-odd km/h where I was doing 20-odd. Ah well.
Still, on the Zenium I felt like I could just keep going all night, whizzing through the turns where there was enough light, stomping up the hills and using the easy control of the disc brakes when it was too dark to risk going flat-out downhill. Lovely stuff.
Frame & fork
The Zenium SL's frame is made from butted 6066-T6 aluminium alloy tubes. This has a slightly higher fatigue strength than the more common 6061-T6 aluminium, so less of it is needed to make a frame. Vitus uses 6066 for bikes designated SL – others are made from 6061.
Up front is an all-carbon fork with a tapered steerer.
Both front and rear dropouts take thru-axles and there's clearance for 30mm tyres, though going that fat won't leave much space under the fork crown; the back end is roomier.
Our 56cm Zenium SL has a reach of 387.8mm and stack of 566.6mm (stack and reach are the vertical and horizontal measurements from the centre of the bottom bracket to the top of the head tube). That's at the racy end of the endurance bike envelope, but there's 3cm of spacers if you want the bar higher.
Mechanics will be pleased to hear that the bottom bracket is threaded and the gear cables run outside the frame, so you won't have to deal with press-fit creaks or hassling internal cables into the frame at replacement time. The brake hoses do run tidily inside the frame.
For a bike that's billed as having 'all round…capabilities' the Zenium SL's frame has one mystifying omission, and that's mudguard provision. There are no eyelets on the frame, and no seatstay or chainstay bridges, so the only mudguards likely to fit without bodging are Crud Road Racer Mk 3s. They'll do the job, but it would be nice to have more options.
A complete Shimano 105 groupset takes care of going forward and stopping, and it's all very slick, as we've come to expect. The gears click smoothly and easily from sprocket to sprocket and the front mech chucks the chain up on to the big ring with considerable oomph.
The Shimano 105 hydraulic disc brakes are undoubtedly a standout feature of the Zenium. They provide powerful and easily controlled braking, with no sign of rubbing or any other irritating behaviour. On a ride that involved a section of downhill bridleway I was able to keep my speed under control with just one finger on the levers and minimal force. They really are a substantial improvement on rim brakes, not because you can brake harder, but because it takes less effort to achieve the same braking power, so controlling speed on long or technical descents is a doddle.
Because there's a hydraulic master cylinder in there, the 105 brake/shift levers are longer than those for cable brakes. That lengthens the reach to the hoods and made it easy for me to get the rangy riding position I prefer without changing the stem. That might mean riders who don't have a silly long back will want a shorter stem.
The Vitus stem connects to a Vitus Compact handlebar with 128mm drop and 72mm reach. It also has an unusual rearward sweep from the centre to the brake levers, which doesn't seem to make any difference to anything, aside from moving the levers back a couple of millimetres, but always made me think the bar was bent.
The Vitus saddle and my bum did not get on. It wasn't agony, but it was far less comfortable than my preferred Fizik and Brooks Cambium seats, so after a couple of rides I swapped it out.
The Zenium rolls on FSA Team 30 wheels. These are very similar to the Vision Team 35 wheels Stu reviewed in 2016, but as the name suggests they're slightly shallower. The Team 30s have a reputation for being a tight fit with many tyres, but I had no problems with either the Michelin Pro 4s fitted or the Continental Grand Prix 4000S II I fitted to the rear wheel when the Michelin sustained a fatal puncture.
The Team 30s' slight aero shape seems to contribute to the Zenium's overall feeling of easily achieving and holding speed. They're not up there with the startling extra speed you get the first time you descend a steep hill on 60mm rims, but they feel a bit faster than bog-standard box-section wheels.
At a claimed 2,100g a pair they are heavy, though. You could lop off half a kilo or more with a wheel upgrade. On the other hand, the rear wheel survived an almost-instantaneous tyre deflation completely unscathed. These are tough wheels. For crappy British road surfaces, that's a bonus.
This is the 2017 version of a bike Stu reviewed in 2016 and I think the changes warrant the extra half star I've awarded it. The hydraulic brakes are superior in feel and modulation to the 2016 bike's TRP Spyres, the wheels are bombproof, and the tyres are a step up.
The price has actually dropped too, with the 2016 bike listed at £1,300, the 2017 at £1,250. Even better, you can now get the 2017 bike for £1,125, which is excellent for a bike with a full 105 group and hydro discs. When almost every bike out there has gone up 10-25% since 2016, that alone is almost enough to get it an extra half star.
It's great fun to ride too: racy but without being a hectic handful, its behaviour owes more to European stage race bikes than super-quick-turning criterium bikes.
And, of course, it's orange. If you could fit standard mudguards to it, it'd be a near-perfect all-weather all-rounder.
Fast, fun, and hugely orange, with the stopping reassurance of disc brakes
road.cc test report
Make and model: Vitus Zenium SL Disc
Size tested: 56cm
About the bike
State the frame and fork material and method of construction. List the components used to build up the bike.
The frame is 6066-T6 aluminium alloy, made into butted tubes and welded together.
The fork is T700 HM-UD carbon fibre, including the steerer
Chainset: Shimano 105 5800, 50tx34t
Bottom Bracket: Shimano 105 5800 (BSA)
Brake/Shift Levers: Shimano ST-RS 505 Hydraulic Disc
Front Derailleur: Shimano 105 5800, 31.8mm band
Rear Derailleur: Shimano 105 5800
Cassette: Shimano 105 5800, 11-speed, 11t-28t
Chain: KMC X11, 11-speed
Rims: FSA Team 30 Disc Brake
Front Hub: FSA Team 30 Disc Brake 100mm x 15mm QR through axle
Rear Hub: FSA Team 30 Disc Brake, 135mm x 10mm QR
Spokes: FSA Team 30 Disc Brake
Tyres: Michelin PRO 4 Service Course, 700c x 25c
Front Brake: Shimano BR-RS hydraulic disc, 160mm rotor
Rear Brake: Shimano BR-RS hydraulic disc 140mm rotor
Handlebars: Vitus compact, 6061 double butted Alloy, 128mm drop/72mm reach
Headset: Token A83M-15 integrated, 1.1/8" – 1.5"
Stem: Vitus, 3D forged 6061-T6 aluminium, +/- 6 degree rise
Seatpost: Vitus UD carbon, 2D forged head, 15mm offset, 27.2mm x 350mm
Seatclamp: Vitus bolt
Tell us what the bike is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about the bike?
Chain Reaction says:
Boasting disc brakes and ample tyre clearance - you can run up to a 30c tyre - the Zenium SL has its widest appeal yet! Choose between road, gravel, or both, on this lightweight and durable aluminium bike. Also featuring a full carbon disc brake specific fork with 15mm through axle, Shimano 105 groupset and hydraulic disc brakes, FSA Vision Team 30 Disc Brake wheelset, and Vitus' own finishing kit.
Super Light 6066-T6 Triple Butted Alloy Frame with T700 HM-UD Carbon Fork
The Zenium SL frame features a fantastically light 6066-T6 triple butted alloy tubeset with smooth welds. Up front, a tapered headtube and oversized tubing culminate in precision handling. The semi-sloping endurance geometry offers a balanced, comfortable ride.
Vitus Zenium Road Bike: Shimano 105 Groupset
The T700 HM-UD disc brake specific full carbon fork features a tapered carbon steerer for increased steering precision with reduced road buzz from rough road surfaces. A 15mm through axle provides enhanced braking performance and improved handling to counteract the brake forces that are transmitted through one side of the fork.
Shimano Groupset for Any Adventure
Equipped with a Shimano 105 groupset and hydraulic disc brakes, the Zenium SL also comes with tyre clearance up to 28mm wide tyres the new Zenium SL offers great performance on any terrain.
Frame and fork
Tell us about the build quality and finish of the frame and fork?
Tidy welding, lovely loud paint.
Tell us about the materials used in the frame and fork?
Well-executed aluminium and carbon fibre.
Tell us about the geometry of the frame and fork?
Somewhere between racy and endurancy, which results in a fun ride that's not a razor's-edge dynamics handful.
How was the bike in terms of height and reach? How did it compare to other bikes of the same stated size?
It's a shade longer and quite a bit lower than most endurance bikes, but a bit taller and shorter than a full-on race bike. It's a really well-executed middle ground.
Riding the bike
Was the bike comfortable to ride? Tell us how you felt about the ride quality.
I did a 95-mile day on it and was perfectly happy.
Did the bike feel stiff in the right places? Did any part of the bike feel too stiff or too flexible?
Yep; it's hard to go wrong with fat aluminium tubes in this respect.
How did the bike transfer power? Did it feel efficient?
Was there any toe-clip overlap with the front wheel? If so, was it a problem?
There's a bit of toe overlap, but it's only a problem when messing about at very low speeds.
How would you describe the steering? Was it lively, neutral or unresponsive? Just on the quick side of neutral, which happens to be exactly how I like it.
Tell us some more about the handling. How did the bike feel overall? Did it do particular things well or badly?
Planted and accurate with just enough willingness to be chucked into corners to make it fun.
Which components had the most effect (good or bad) on the bike's comfort? would you recommend any changes?
The saddle didn't fit my arse at all, which was a bit annoying when I accidentally did a 95-mile day on it. I grew to like the combination of bar and shifters, though the bar shape is a bit disconcerting.
Tell us some more about the drivetrain. Anything you particularly did or didn't like? Any components which didn't work well together?
Shimano 105 shifts quickly and easily. For a bike that's supposed to be an all-rounder capable of long rides and even a bit of dirt, the 11-28 cassette is an odd touch; an 11-32 would be more appropriate.
Wheels and tyres
They're not light, but they still feel quick, and they're tough as nails.
Even by disc brake wheel standards, they're heavy.
Very decent go-faster tyres
Very nice to get tyres of this quality on a bike that costs not much over a grand.
Did you enjoy riding the bike? Yes, very much.
Would you consider buying the bike? Yes
Would you recommend the bike to a friend? Yes
Use this box to explain your score
I really enjoyed riding the Zenium SL. It has faults, yes, but none of them are remotely deal-breakers and they don't detract from the massive fun factor on offer here from the precise handling frame and the superb control afforded by the hydro discs.
About the tester
I usually ride: Scapin Style My best bike is:
I've been riding for: Over 20 years I ride: Most days I would class myself as: Expert
I regularly do the following types of riding: commuting, touring, club rides, general fitness riding, mountain biking
Our official grumpy Northerner, John has been riding bikes for over 30 years since discovering as an uncoordinated teen that a sport could be fun if it didn't require you to catch a ball or get in the way of a hulking prop forward.
Road touring was followed by mountain biking and a career racing in the mud that was as brief as it was unsuccessful.
Somewhere along the line came the discovery that he could string a few words together, followed by the even more remarkable discovery that people were mug enough to pay for this rather than expecting him to do an honest day's work. He's pretty certain he's worked for even more bike publications than Mat Brett.
The inevitable 30-something MAMIL transition saw him shift to skinny tyres and these days he lives in Cambridge where the lack of hills is more than made up for by the headwinds.